CanTransfer function checks if "to" and "from" values are
correct script hashes. If one of these values is correct and one
incorrect, then function returns false positive result. It uses "and"
operator which requires both "to" and "from" script hashes to be
incorrect to fail transaction.
Instead transaction must fail if at least one argument is incorrect,
so it should be "or" operator.
neo-storm has developed more wrappers for syscall APIs, so they can and should
be used as a drop-in replacement for pkg/vm/api. Moving it out of vm, as it's
not exactly related to the VM itself.
